Question

prove that if a body thrown vertically upward then time of ascent is equal to the time of discent

Answer 1

Answer:

Time of Ascent:

The time taken by body thrown up  to reach maximum height h is called as time of ascent.

Let t₁ be time of ascent.

at maximim height , its velocity is zero, V=0

hence , V=u-gt

0=u-gt₁

t1=u/g ------------- (1)

Time of descent:

after reaching the maximum height, the body begins to travel downwards and reaches the ground.

The time taken to by a freely falling body to touch the ground is called time of descent.

Initial velocity for downward journey is zero  , u= 0

let t₂ be time of descent.

s=ut+1/2 gt²

h=0+1/2gt₂²

t2=√2h/g

but, h=u²/2g

so, we get

t₂=√2u²/2g

   =u/g---------------(2)

from equation 1 and 2 we can say

t₁=t₂

the time of ascent is equal to time descent in the case of bodies moving under gravity.

hope it's help you